Removing or inhibiting the formation of ice is an activity that can be useful, or necessary in a wide array of circumstances.
For example, the formation of ice from moisture present in a mass of particulate material, such as coal or coke, has long been a troublesome problem confronting the collection, storage, transportation and use of such particulate material. As moisture present with the particulate solids freezes, the ice that is formed acts as a strong adhesive contributing to the formation of coherent masses of particles. The so-formed masses significantly interfere with attempts to process the particulates through normal solid handling techniques.
Other instances where the formation or accumulation of ice creates problems include the formation or accumulation of ice on roads and other outdoor surfaces, such as sidewalks, parking lots, driveways and the like; the formation or accumulation of ice on exposed surfaces of airplanes, on airport runways and the like, the formation or accumulation of ice on plants, on fruits and on vegetables to name but a few potential deicing or anti-icing applications.
The prior art has proposed a variety of compositions, alternatively referred to as freeze conditioners (freeze conditioning compositions or agents), de-icing compositions or agents, anti-icing compositions or agents, low temperature salt out prevention agents, and freeze control compositions or agents, that can be used in such applications to inhibit the formation and/or remove the accumulation of ice. These materials work by reducing or depressing the freezing point of water, (or other dissolved solids in salt out applications) and by interfering with the formation of coherent ice crystals (e.g., inhibiting or terminating ice crystal growth), so that the frozen water is physically weak and more easily fractured. In this regard, we refer the reader to the following non-exhaustive list of U.S. patents describing a wide variety of freeze conditioners: U.S. Pat. Nos. 2,101,472; 2,116,682; 2,373,727; 2,716,068; 3,298,804; 3,624,243; 3,794,472; 4,117,214; 4,225,317; 4,439,337; 4,448,702; 4,599,250; 4,666,741; 4,746,449; 4,778,615; 4,824,588; 4,960,531; 5,429,763; 5,876,621; 5,891,225; 5,980,774; 6,149,834; 6,183,664; 6,506,318 and 6,878,308.
Because no one composition has been universally accepted and because such compositions generally suffer from one or more negative attributes, such as high cost, unacceptable corrosion, limited effectiveness and the like, which limits their utility across the wide variety of potential de-icing and anti-icing applications, the prior art continues to explore the suitability of alternative compositions for deicing and anti-icing applications.
In certain cases, like in the freeze conditioning of combustible materials such as coal, coke and grain, it is desirable that the freeze conditioner also protect the combustible materials from premature combustion. The freeze conditioning and deicing materials of the present invention and materials similar to those described in the present invention have demonstrated, in other applications, the ability to protect the substrate onto which they are applied from combustion as described in the following U.S. Pat. Nos. 4,294,879; 5,710,239; 6,114,491; 6,245,438; 6,369,171; 6,379,814; 6,586,557.